Blast burner



M. F. BETZOLD BLAST BURNER Filed May 16, 1935 April 4, 1939;

f'z-zfc/z'or: Man: Ffieizold III/Z ,7 WW 4/ WW i y W Patented Apr. 4, 1939 UNITED STATES BLAST BURNER Max F. Betzold, Chicago, 111., assignor to Rascher & Betzold, Inc., Chicago, 111., a corporation of Illinois Application May 16, 1935, Serial No. 21,803

4 Claims.

The present invention relates to burners and particularly to that class of burners known as blast burners, and a particular object of this invention is to provide a noiseless burner capable 5- of generating high temperatures suflicient to melt glass of the type used for oven ware and laboratory glassware, which melts at a much higher temperature than ordinary glass, and even glass having a much higher temperature than such kinds of glass above mentioned.

Another object of this invention is to provide a burner in which the various gases which are used are thoroughly mixed before being forced out of the nozzle provided on the burner, whereby a more eflicient burning of the gases and a quieter operation of the burner is insured.

Another object of this invention is'to provide a very simple type of burner capable of carrying out the aforesaid objects in which the number of parts necessary is greatly reduced to lessen the cost of manufacture, reduce the opportunity for parts getting out of adjustment, and for insuring more eflicient operation.

Another object of this invention is to provide in a blast burner of this class a mixing chamber into which the gases flow, with a turbulent action so as to be thoroughly mixed before being forced through the nozzle connected to said chamber.

Another object of this invention is to provide a blast burner of the class described in. which the various gases introduced into the burner are introduced in such a manner with respect to the flow of the gases through the burner as to insure a thorough mixing of these gases prior to the ejecting of the same through the nozzle.

More particularly, this invention contemplates the provision of a blast burner having an en.- larged mixing chamber for the gases into which the gases are introduced through the same inlet,

the same having an inlet passage into which the gases are introduced at different distances from said chamber, with the gases introduced at the remoter points at higher pressures than those nearer the chamber, whereby the gases are all swept into the chamber in thepredetermined proportions determined by suitable valve mechanisms. I

Another object of this invention is to provide a nozzle of a very simplified construction and provided at the tip thereof with a plurality of openings, the material having low heat conductivity, whereby to reduce the hazard of any strike-back of the flame and to prevent the heating of adjacent portions of the nozzle which support the low heat conducting material at the tip thereof.

Another object of this invention is to provide a nozzle of the type set forth in the precedin paragraph in which the perforations in the tip 6 are arranged in the material of low heat conductivity in such a manner as to have those openings nearest the remaining supporting portions of the nozzle spaced considerably therefrom, whereby to prevent heating of those supporting 10 portions.

Another object of this invention is to provide a gas burner of the classdescribed in which there is a mixing chamber remote from the tip of the nozzle and into which the gases are introduced from a-conduit having lateral passages extending therefrom at different distances from the chamber, the passages at the more remote portions of the conduit being under higher pressures than those nearer the said chamber. 20

In the drawing:

Fig. 1 represents a side elevation of a burner embodying my invention, with parts thereof shown in central longitudinal cross-section;

Fig. 2 is a cross-section taken along the line 25 2-2 of Fig. 1; and

Fig. 3 is a cross-section taken along the line 3-3 of Fig. 1.

In heating certain types of glass, particularly those having a high melting point, it is neces- 3o sary, especially when using ordinary illuminating gas, to provide not only air but oxygen as well in order to get a sufiiciently hot flame from the burner to melt the glass or soften the same when working the glass into various shapes, such as 35 for laboratory glassware and the like.

The disadvantage with previous burners of this type has been that they have been exceedingly noisy and render conversation in ordinary tones impossible when even one of said burners is being 40 operated. In some glass-working establishments, hundreds of these burners are apt to be in use at one time and in a relatively small area, thus producing a din which is very distracting to the workers, as well as very detrimental to their health as in time it affects their hearing. Furthermore, it makes conversation very diflicult, thus handicapping the workers or those giving instructions to the workers as to their work. While this has been recognized as an undesirable feature of previous types of burners, nothing has apparently been accomplished in the way of reducing the noise made by this type of, burner.

With the burner disclosed in this application, not only is the. burner rendered practically noise- 5 less but also the temperature of the flame has been substantially increased far beyond temperatures which have been obtained from this class of burners previously.

In order to reduce the noise caused by the burning gases, applicant has devised a blast burner in which there is a relatively large mixing chamber which is substantially free from obstructioi'is and into which theyaridus gases are introduced and thoroiighly mixed before passing on to the nozzle provided at one end of the chamber. The nozzle itself is also unobstructed except at its tip where a plate or the like of low heat conductivity is provided and through which there are a number of small perforations grouped so that the outermost ones of the same'are spaced a substantial distance from the portions of the nozzle which support said plate.

I have illustrated in the drawing one form of my invention in which there'is provided a base 49 of ny .sies r d masse sesupp in t burner and indicated generally by thereference n meral I I. The burner has at tlie-bottomthere-v V b: a spherical D 1 E 1 2 'gatin 'yrith n a spherin al t e 1 isl bh ter in 'ical assessment thebase'lll. 'fl'he spherical projection is ghld'i in th rec'ess bylmeanscf a Isplit nut l FhrQ-dBd into Phlbflse [0, is clearly illustrated in F 1'. {l'he split 'nut 4 'is'tightened swam mam n li il H any permitted angu arjpssm n' with respect .to' the basel'llfbutpreferably'does not firmly loclcthe burner in that po sitipnwhereby, when forceis applied on' the punter, the .liiir'ner may be. adjustedto'variousiangularlposi ions with respect filthgbase: V v.

Aboye the sphericalprojection J2, and formed w th, is i=1" tubular conduitfli L per "end contiguous" with the chamber J, of the ".Asshown'in the drawingftheponduit' 1,5, "wlii'ch' I' shall term the inlet condiiitfihtroduce's thQgases latfb'ne'er'id ofthe ch mber l6, ,andsince the Idiam'terof thebhainb eri'lt is ,larger'tl'ia'n that "oftheiinlet t 1E b ia fir b t e, as s i de eeed r r g'o fsaidgases betorejthe same' ente'r -the no'zile I1, "scrje threa'dedat ltt to. the opposite .end of .the chamber 'I'S'.

' Three 'branchconduits extend laterally irom the/ inlet conduit is, as is illustnaftediin '1.

Branch conduit ,l 9 connected to a source 01' illum natin s' n land hi a "i Ied into the inlet" conduit ,nearest the mixing chamber I.6. The 7 branch i's conn'ected tda .source of air'underpiiessiire', andlthi's air is'fed into the inlet ,condiiitlat a pcint more remote from the mixing',}chamb er 16L fOjxygen is introduced throughgth'e brancH-CQ idIiit 1| into the inletflconduit 5 ratgapoin'tfstill moreremote from the chamber.

.P) ll i 9 3 1 e r i e e l ter than the press re on ,the air, which in turn greater than the pressiire on the illuminating gas, and it isrf or this .reason that I preferably arrange the branch conduits in their relative m o s owniii he d aw Thesrea er pres onthe'oxy n cau t e ame o. we p the air enteringithe-inlet conduit through .the branch. passage 2.0. in adirection toward the mixing .chamber,. and both of these gasesin turn do likewiseiwith the illuminating gas entering the inlet-conduit l -'5'throu g h thev branch conduit [9.

If, forinstancathe' arrangement of the branch conduits was reversed from that show nffthe greater velocity and pressure of the oxygen -entering thro'ugh the upper" branch passage 1 9 pf syphoning action for the branch passages l9 and 20, thereby assisting the flow of the illumihating gas and air into the mixing chamber through the inlet conduit I5.

'In each of the passages I9, 20 and 2|,I provide f'needl'e valves 22, 23 and 24, indicated in dotted lines in 1, one of these, namely 22, being illustrated in cross-section in Fig. 3, the other needle valves, 23 and 24, being of similar construction.

The branch passage 19 is provided with a .wallfs ichas 25, having a passage 26 therethroug'h and a'needle valve 2lYoperated by the knurled head ZBandthreaded at29, and is adaptea s jco-operatlwiththe passage 26 to restrict the.fl0w'of' .the gas therethrough, thereby determining theIrate'fat rh thegas may flow through".the branch ,pa agells at this point. The needle yalvesffl, 23 d 24 are each prefe'rably adjusted "so to give the proper propcrtions of the various gases when the passages ISQZDandZl arejother yifsfe unobstructed. one! .narily, when the ,liurneris {not ,being used, it is desirable to provide a ,valvefn jeahs r r'cmsmg thepassages 13, Hand Z'Ildtherjthan .the needle valves 22, 2 3 and 2,, whereby .itbecomes unnecessary to disturbthead justments of [the treeare valves 22, .Ziitrndfl4,.

"In the embodiinhtishown, ,Idhaye illustrated ordinary.plug-ccc,ks .310, 3| and Elihaving' lateral passag n l t fi fie arran edtso a llidb in alignment with the axes ,bff the [branch passages '1 a, 2n and 2| when therii g-l ks gare'onm their on position whereby, except" ,for the needle tvlalrem ebran saus e r une s i t the ofi po s ition of 'thesiejpl jig-c 'ckfs; the flow of gases through the branchfpassages' I is .fprevente'd. 'Ifhe nczj'zle H is preferably slightly tapered iewars t t ither t Yd lprbl i ifidll i hf l p 3, m de of mate a hIaYmsi ati i l -mw heat conducti i an i th 'Ismbdd s o n I ha lus rat d ha nn ,b i l mad 'pf p rcelain, silica cr similar' material having the above mentioned I property. Obvious'1y,,oth'er in aterials can be used for thisliurposejandgthereforeLIdo that purpose.

ns'is seen inlifig. 1, andas more,clearly illustrated inFig. 2, th e porcelain is pr ovide'd with a series of small perforations 3'6 grouped so that the outermost ones of the perforations are spaced appreciably from the metal flange 34 and bead is Spaced rem th l n i ia d, n i i i fio of heat of the fiajme'to the Supporting portions or the nozzle throiigh the porcelain 33, which is o ll wh a 'cqndi =i iv i l.is ni c fi ll f iir r i This is important in 'view'of the fact that'p'heating of the parts of the nozzle may, cause a premature burning of the gases within the nozzle instead of outside the same, this being commonly known as striking-back. Obviously, any striking-back of the flame, accompanied by the resultant explosion, is detrimental to the structure of the burner and requires the cutting off of the supply of gas, air and oxygen, and then, after the parts have cooled down somewhat, a relighting of the burner itself.

The nozzle, as is clearly illustrated in the drawing, is smaller in diameter than the diameter of the mixing chamber l6, whereby the velocity of the gases through the nozzle is greater than through the mixing chamber and is ejected with suflicient force through the perforations 36 as to cause an efficient burning of the gases emerging from the nozzle.

The burner is provided with a pilot tube 31 which leads off the branch passage l9 to the left of the needle valve 22, and is provided with a plug-cock 38 of any type, to control the flow of the illuminating gas therethrough. The pilot tube terminates adjacent the tip of the nozzle and is provided with an outlet opening 39 through which the illuminating gas emerges from the pilot tube. Such pilot tubes are common in this art and are, of course, for the purpose of maintaining a small flame near the tip for lighting the burner and for keeping the same lit in case the flame should temporarily be blown out. This pilot tube is supported by braces 40 secured to the outside of the chamber I6.

In using this burner, the branch passages I9, 20 and 2| are connected, as described, to their various sources of supply and the plug-cock 30 is opened to permit the illuminating gas to pass into the chamber and out of the nozzle, the pilot light having previously been lit and causing the ignition of the illuminating gas as it emerges from the nozzle. Thereafter, the plug-cocks 3| and 32 are opened successively or simultaneously to assist in the complete burning of the illuminating gas and for producing the higher temperature flame necessary for the purposes for which this burner is adapted. If the adjustment of the needle valves 22, 23 and 24 is not proper under the existing pressures in the passages I9, 20 and 2|, the same may be manipulated to change the flow of the gases therethrough to secure the proper flame for heating and/or melting glass and like substances.

The device, while extremely simple, is nevertheless efficient and accomplishes what has not been accomplished by previous burners of this character; namely, the quiet burning of the gases which enables one to carry on a conversation in ordinary tones even though several of these burners are being operated near the place where the conversation takes place. This is due to the fact that there is a complete mixing of the gases in the chamber IS, a uniform mixing of the gases due to the manner in which the gases are successively introduced in the conduit l5, and to the free, unobstructed flow of the gases through the burner and the emerging of the gases in a plurality of finely divided streams which flow substantially in the same direction as the flow of the gases through the nozzle ll.

Where, as previously, the gases are mixed near the tip of the nozzle, the turbulency of the gases creates a non-uniform flow of the gases through the tip of the nozzle, thereby preventing uniform burning of the gases outside the nozzle. Furthermore, when gases are mixed close to the tip of the nozzle, as in previous devices, there cannot be a thorough mixing of the gases before the same emerge from the nozzle and as a result there is an explosive action in the burning which causes excessive noise. Furthermore, by properly mixing the gases before they are passed through the tip of the nozzle, a greater percentage of the combustible materials are burned and the result is a much hotter flame than has been possible with burners of this type previously. Whereas with previous types of burners of this character which are now in common use in shops where glass working is done, the temperatures created by the flames of such burners have only been barely capable of meeting the minimum requirements for heating glass such as that used for oven ware and the like, the burner shown in this application is capable of not only meeting the maximum requirments for the heating of such glass, but has also been able to reach requirements necessary for heating glass such as quartz glass which has a melting point of from 1700 to 1800 degrees centigrade, which is not possible with known types of burners which are now on the market and being used in glass-working establishments.

I do not wish to limit myself to a burner for burning only illuminating gas or the like, since any of the compressed or liquefied gases may be used for this purpose. Nor do I wish to limit myself to a burner in which the particular form of stop-cock or needle valve shown in the drawing is used, as other stop-cocks and valves may be used for accomplishing the same results.

Several nozzles may be supplied for the same burner, each nozzle being of a different diameter at the tip and/or having a different number of perforations, whereby to create the different types of flames desired in this kind of work. Thus, the operator may quickly switch nozzles on the burner to secure the desired flame for the particular work he is doing. The perforations in the nozzles are preferably about the size of pinholes.

Preferably, the burner is made entirely of metal, except for the porcelain tip 33 which might even in some cases be also made of metal having a relatively low heat conductivity as to be quite rigid.

Obviously, those skilled in the art to which this invention pertains may make various changes in the particular arrangement and construction of the parts shown in the drawing without departing from the spirit of this invention, and therefore I do not wish to be limited, except as set forth hereinafter in the claims.

Having thus fully described my invention, what I claim and desire to secure by Letters Patent of the United States is:

l. A blast burner comprising an elongated tube substantially unobstructed throughout its entire length and having an enlarged median chamber forming a mixing chamber, a branch conduit communicating with said tube at a point to one side of said enlarged median portion for supplying inflammable gas and oxygen to said tube and into said median enlarged mixing chamber to produce a whirling motion to the gases when the same are introduced into said median portion, the other end of said tube having a tip of a material having low heat conductivity with a plurality of centrally arranged perforations of relatively small diameter.

2. A blast burner comprising an elongated tube substantially unobstructed throughout its entire length and having an enlarged median portion forminga mixing chamb'erf'a bra r cl i conduit communicating with" said tube at' a point tov one side "of said enlarged median portion for supply: ing inflammable gasj'fan'd oxygen to' said tube and into said'lnedian enlarged mixing chamber to produce a whirling motion to the gases when the same are int'rocl'uced into said media'n'portion, the other 611d of S aid tub e having Of material having w heat conductivity witha plurality" of centrally arrangedlne'rforations or relatively small diameter, said centrallyarranged grou of perforation's being surrounded'by' an"imperforate area oi'materiallygreater width than the spacing of said obeningsffrom each other whereby heat generated adjacent said openings from the resulting burning or the gases will not be transmitted through saidti'p to the adjacent supporting walls of saidtube. d

3. In a" blast burner the combination with a mixing chambenofan inlet conduit communieating with said chamber at one side thereof, a reduced extension; on said chamber at another side thereby; remote from said inlet conduit, a burner ti'p'threon provided with. numerous small perm-moon's therein "through wmeh" the gas mixcr e-129 P rine e s-Pie W fi m said reduced extension on' said chamber at another sideth ereof remote from said inlet conduit, a burner tip thereon provided with numerous small periorations therein through which the gas mixture to be burned is adapted to flow from said chamber, and means for" supplying several different aeroform fluids into said inlet conduit, comprising separate ducts for introducing an inflammable gasand an oxidizing medium into said inlet conduit, theduct carrying the aeroform fluid under the higher pressure being arranged at a point along said inlet'c'onduit more remote from said chamber than the duct whichvintroduces the aerqfo'rm fluid under the lesser pressure.

MAX F. 'BET ZOLD. 

